<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style>
        .li_level1{
            float: left;
            width:200px;
            text-align: center
        }
    </style>
    <script>
        function init(){
            let abuttons=document.querySelectorAll(".btn_a");
            [...abuttons].forEach((item)=>{
                item.addEventListener("click",(event)=>{
                    event.preventDefault();
                    let url=item.href.substring(item.href.lastIndexOf("/")+1);
                    console.log(url);
                    switch(url){
                        case "emp": 
                            document.getElementById("insertPoint").innerHTML="普通员工界面";
                            break;
                        case "manager" :
                            document.getElementById("insertPoint").innerHTML="管理员工界面";
                            break;
                    }
                    history.pushState({},"",url);
                },false);
            });
        }
        window.addEventListener("load",init,false);
    </script>
</head>
<body>
        <ul style="list-style: none">
            <li class="li_level1"><a class="btn_a" href="emp">员工</a></li>
            <li class="li_level1"><a class="btn_a" href="manager">管理员</a></li>
        </ul>
        <br>
        <hr>
        <div id="insertPoint"></div>
    </body>
</html>